The slower courts may not be helping Roger Federer, but John Millman is cashing in as the last Australian standing at the US Open as he bids to set up a dream showdown with the great Swiss.

After a trip to tennis hell and back, Millman takes on unseeded German Philipp Kohlschreiber on Sunday morning for a place in the last 16 at a grand slam for the first time.

Victory over the world No.37 and a 13th win for Federer in as many meetings with Feliciano Lopez will guarantee Millman a centre-court shot at the 19-times grand slam champion.

Playing on an injury-protected ranking in his comeback from groin surgery, Millman is trying to stay in the moment, focusing only on Kohlschreiber after taking out Australian No.1 Nick Kyrgios and Tunisian Malek Jaziri.

But the 28-year-old admits he’s finding the conditions at Flushing Meadows to his liking.

“I have felt really good here. The conditions here at the US Open are definitely slower than they have been in the past, the ones that I’ve played before,” Millman said.

“That’s probably due to the weather. It’s not quite as hot and the courts might be slightly rougher and the balls don’t seem to flying through.

“That, all in all, really suits me and I felt comfortable pretty much from the start.”

While Federer has had to negotiate back-to-back five-setters in the first two rounds for the first time in his record 65th grand slam appearance to reach the third round, Millman has dropped only one set.

He lost his only previous meeting to Kohschreiber 7-6 (7-5) 6-3 on an indoor hard court in 2015.

“He is a great ball-striker from the back of the court, got that beautiful one-hander that he can pull both ways and he has established himself as top 30, top 40 for a long, long time,” Millman said.

“So he has plenty of experience at this level. It is going to be a tough game but I am now in the third round and with every round that progresses, the more confident I get.

“If I can play how I have played the last couple of matches, I am sure I can give it a really good crack.”

As he savours his moment in the sun, Millman recalled the dark days on his way back from two shoulder reconstruction. Two particular tournaments stick out.

“Potesht in Romania, I really struggled with,” he said. “I drove for ages through cane fields and I thought I was going to get mugged. It was really dodgy.”

He also vowed to avoid returning to Gimcheon until desperation forced him back to South Korea.

“I had a look at the schedule as to where I could go that wasn’t too far away from Australia and I saw four $10,000 Futures,” Millman said.

“Now $10,000 Futures are the lowest of the low in Gimcheon, so I rocked up there and wondered, ‘What am I doing?’.

“It was on my birthday. I got to the quarters and after my first match, I actually had what is called an instability episode where your shoulder, because it hasn’t got that conditioning, it pops out of the socket and pops back in.